PROJECT SUMMARY The primary goal of this R34 proposal is to conduct pilot testing of a new intervention for college student substance use. Risky substance use among college students is widespread, and associated with numerous adverse consequences. Although brief motivational interventions (BMIs) have been widely adopted by colleges to address risky alcohol use, most studies find only small to moderate effects, with a review of college student drinking interventions noting that ?significant enhancement of personalized feedback intervention efficacy has not been observed in over 15 years of study? (Miller et al. 2015). Current interventions focus on students? current substance use, and largely do not address underlying risk factors and the pathways that lead students to use. There is compelling evidence that students use/misuse alcohol for different reasons, and that externalizing, internalizing, and physiological factors strongly predict college students? substance use and problems. The fast-growing field of personalized medicine is harnessing our growing knowledge about underlying etiological factors to provide individuals with specific information about their unique risk profiles and personalized recommendations, in order to motivate and enable individuals to better self-regulate their health. With this R34 we will evaluate an on-line Personalized Risk Assessment (PRA) for college students that provides feedback about the individual?s specific core underlying risk factors for substance use, and how these factors can lead to substance problems, along with personalized recommendations and resources. The project will capitalize on foundational work from our unique, on-going university-wide research project (Spit for Science; S4S), in which >12,000 students (~70% of five years of incoming freshmen thus far) are being followed longitudinally with surveys assessing substance use and related factors across the college years. From these data we have identified risk factors most strongly related to college students? substance use, and have developed an associated research center that brings together S4S researchers with university administrators and student affairs personnel to translate this research into enhanced university programming and policy. Making use of this extant collaborative network, we will (Aim 1) finalize the editing and programming of our on- line personalized risk assessment platform; (Aim 2) systematically refine the risk questions and feedback tools by conducting four focus groups (N= 40) and an open trial (N=40) with college students with varying risk profiles, and one focus group with college wellness staff and service providers; and (Aim 3) preliminarily evaluate the efficacy of the PRA in comparison to an assessment only control group, a standard BMI, and a PRA+BMI condition to test whether there are additive or interactive effects, using a randomized controlled design of N = 300 freshman with measures of substance use and academic functioning collected at 3 time points across the freshman year. College represents a unique opportunity to intervene and have positive life- course altering health benefits for a significant, and increasingly diverse portion of the population.